How to fix 'Runtime Error'

Runtime Error Attempt to invoke virtual method ‘void android.widget.FrameLayout.setVisibility(int)’ on a null object reference Note: You will not see another error reported for 5 seconds.

why is there an error in the application that I made, please check

8 posts were merged into an existing topic: [FREE/PAID] BottomMenuZ - Create Animated Bottom Navigation Menu Easily!